Thank you for your reply. >* It's worth to set nimage equal to the number of q-points *>* in the phonon >calculation? * not necessarily so. Different wave-vectors may have different workloads: not by order of magnitudes, but a low-symmetry wave-vector may easily take 5 times more CPU than a high-symmetry one.
But still as far as I understand is there any cost of doing it? Am I loosing somthing by puting nimage=number of q-points in the dyn0 file? I understand that some of the parallel images will be finished before the other, But there is nothing I can do to speed it even more. >* In addition I want to ask how the complexity of the phonon calculation*>* >depends on the number of the k-points (in the PW calculation) * roughly linearly, but the number of actual k-points in phonon calculations depends upon the symmetry and the wave-vector >* and how the number of k-points affects the accuracy of the phonon*>* >calculation. * more or less (more rather than less) in the same way as it affects the calculation of other structural properties; quantities related to the electric field (effective charges and dielectric tensors) tend to converge more slowly with the number of k-points P. -- Paolo Giannozzi, Dept. Chemistry&Physics&Environment, Univ. Udine, via delle Scienze 208, 33100 Udine, Italy Phone +39-0432-558216, fax +39-0432-558222 On 7 October 2013 09:48, Uri Argaman <argamanu at post.bgu.ac.il> wrote: > It's worth to set nimage equal to the number of q-points in the phonon > calculation? In addition I want to ask how the complexity of the phonon > calculation depends on the number of the k-points (in the PW calculation) > and how the number of k-points affects the accuracy of the phonon > calculation. > > thank you > > Uri Argaman > > Ben-Gurion University, Israel > -------------- next part -------------- An HTML attachment was scrubbed... URL: http://pwscf.org/pipermail/pw_forum/attachments/20131010/1aa891b1/attachment.html